Seismic Analysis of 3D Framed Building

Generally RC framed structures are designed without regards to structural action of masonry infill walls present. Masonry infill walls are widely used as partitions. These buildings are generally designed as framed structures without regard to structural action of masonry infill walls. They are considered as non- structural elements. RC frame building with open first storey is known as soft storey, which performs poorly during strong earthquake shaking. Past earthquakes are evident that collapses due to soft storeys are most often in RC buildings. In the soft storey, columns are severely stressed and unable to provide adequate shear resistance during the earthquake. Hence a combination of two structural system components i.e. Rigid frames and RC shear walls or Rigid frames and Bracings leads to a highly efficient system in which shear wall and bracings resist the majority of the lateral loads and the frame supports majority of the gravity loads.

Performance of RC Cast-in-Place Buildings During The November 26, 2019 Albania Earthquake

This paper documents performance of cast-in-place reinforced concrete (RC) buildings in the Durrës during Albania earthquake of 26th of November 2019 (MW 6.4). Both mid- and high-rise RC buildings were affected by the earthquake, experiencing structural and/or non-structural damage and even collapse in some cases. The authors performed a reconnaissance study after the earthquake and were involved in seismic assessment of buildings in the affected area. Besides the observations related to physical damage related to RC buildings, the paper also presents results of a statistical analysis of damaged RC buildings in the Durrës city. The discussion in the paper is focused on damage patterns and failure mechanisms that are relevant for the seismic response of RC structures. Most common damage pattern is related to masonry infill walls, which experienced damage and failure in some cases, and affected the performance of adjacent RC columns due to the infill/frame interaction. Taller RC framed buildings (10 storeys and higher) were expected to have RC shear walls; however, these walls were reportedly absent in the damaged buildings of this type. In some cases, masonry infill walls (instead of RC shear walls) were used in the elevator shaft areas, which resulted in inadequate seismic performance. Two case study buildings were presented in detail to illustrate seismic behaviour of cast-in-place RC buildings. The case study is based on field observations after the earthquake and a detailed seismic assessment study. Finally, relevant lessons and recommendations are presented in light of the observed performance of RC buildings.